Question

Solve the missing variable. Show your process please because I did the other three on my homework sheet but I really struggle with math. Will definitely give brainly because this means a lot :)
-8.4b - 4.2 = 12.6

Is this -2 or?

Answer 1

Follow these steps:

-8.4b - 4.2 = 12.6

Add 4.2 on both sides:

-8.4b = 16.8

Divide by -8.4 on both sides to give you the final answer of:

b = -2

So you're answer is indeed correct! Hope this helps and that the steps are clear enough!

Answer 2

The big intention behind every step you take in these "find the value of x" problems is to isolate the x by doing PEMDAS in reverse and using the opposite operation. So I would do first is add the 4.2 on both sides. This is so that the 4.2 on the side of the x is canceled out. This makes
$- 8.4b = 16.8$
From here, since the opposite of multiplying is dividing, you divide both sides by -8.4. You can use a calculator to find the answer but you get
$b = - 2$